In an integrated circuit system (such as microprocessors, application-specific integrated circuits (ASICs), system-on-a-chip (SOC) devices, Very Large Scale Integration (VLSI) chips, or other computer processor system), a clock signal is used to define a time reference (e.g. clock rate) for the movement of data within the integrated circuit system. Typically, the clock signal controls the functions of various parts of an integrated circuit by propagating the clock signal to the various parts. Clock jitter occurs when the clock signal is not consistent in the periodic clock pulses. Clock skew occurs when clock pulses arrive to various parts of an integrated circuit at different times. Clock jitter and clock skew are problems which affect the proper operation of the integrated circuit. Recent efforts have been made to minimize jitter and skew and to reduce the power needed to send a clock signal to various parts of an integrated circuit.
A global clock signal may be propagated to the various parts of the integrated circuit using a clock distribution network (such as a clock tree, or clock mesh). A clock distribution network often takes a significant fraction of the power consumed by an integrated circuit. More recently, traditional clock distribution networks have been improved through the use of resonant clocking. Resonant clocking involves the recycling of energy between a capacitor and an inductor. The energy is exchanged between the capacitor (C) and the inductor (L), causing changes in the magnetic field. The changes in the magnetic field cause the energy to be exchanged in the other direction. Resonance occurs due to the periodic exchange of energy over circuit between the capacitor and inductor (also referred to as LC circuit, LC oscillator, LC tank, or tank circuit).
Resonant clocking requires less power to maintain a consistent clock signal. Resonant clock mesh circuits take advantage of resonant clocking in a group of LC circuits linked to a clock distribution network. Traditionally, resonant clock mesh circuits have been designed for a particular resonant frequency based upon the electrical characteristics of the LC circuits. A resonant frequency of the resonant clock mesh may be associated with a particular clock rate of the integrated circuit.